Your arguement about pluripotent embryonic stem cells is a distinction without a difference. A pluripotent stem cell (which differs from a skin cell based on internal chemistry and little else) derived from skin cells forms a blastocyst that is biologically indistinguishable from a blastocyst created by fertilizing an ovum. The same cells (either from skin cells or from a fertilized ovum) can be directed via a sequence of hormonal baths to become an ovary, skin, liver, neural tissue, corneas or even a fetus. That we don't have all the sequences fully sorted out doesn't change the fact that this is fully viable.

so your arguement about embryonic stem cells derived from skin cells is a distinction without a difference. Presented with two samples - one from fertilized ova and the other from activated stem cells derived from skin, a biologist would have no way of distinguishing between the two without gathering more information. That means they are by definition: indistinguishable.

Nor am I arguing a strawman when I point out that your tumor arguement is based in the harm the tumor does to the host woman:

Unlike other entities of the mother’s body, or other cell configurations, the fetus does absolutely nothing biological on behalf of the mother

So far tumor and fetus are indistinguishable by YOUR criteria. I picked a tumor because you make the claim of "unlike other cell configurations" and a tumor is simply an "other cell configuration". So then you added

Obviously, a tumor is a case where the mother’s body malfunctions to generate cells

Now you don't explain how one identifies "malfuction" in cells. The reasonable conclusion is that those cells begin to function in a manner that is harmful to the host woman. And again, that is indistiguishable BY YOUR CRITERIA from a fetus. So yeah the tumor example undermines 3 of your 3 stated criteria in this post as to why there are "two entities" in the case of a fetus and the host woman.

IOW your "plenty of room for discussion" really leaves us with no logically consistent points to discuss.

Your assertion that fetuses have a "life of their own" unlike tumors, is nothing more than an assertion.

• Both require nutrition and organ function of the host woman to continue to undergo cell respiration, division etc.
• Both cannot continue to function if the source of the host woman's blood is cut off (that's how modern "targetted therapies" work BTW)
• Both can be artificially supported outside the host woman's body.

You haven't made the case for a biological distinction.